The present invention relates to an improved method of differential diagnostic sperm examination and the use of prestained slides in the employment of that method.
The principal components of sperm are the spermatozoa and the round cells, which in turn are made up of leukocytes and the cells of the spermiogenesis. The morphological examination of spermatozoa is of great importance in andrology. Differentiation between normal and pathological sperms yields useful information in fertility examinations. Precise differentiation of these normal and pathological forms under the microscope is possible only when the sperms have been prestained. A number of staining methods have been developed (such as the Mayer-Stiasny method and the Papinicolaou method), but they are usually very complicated in practice.
Thus, in the Papanicolaou method (see C. Schirren, Praktische Andrologie, Berlin 1971, page 20), for example, the smears are air-dried for 24 hours and then fixed for 5 minutes in a 1:1 mixture of 95% alcohol and ether. The smears are then subjected to an extensive treatment which comprises the following successive steps:
Immersion for 10 sec each in a descending alcohol series (80%, 70% and 50%);
10 sec in distilled water;
3 min in a hematoxylin solution; 10 min or longer in running water; 2 sec in 0.5% hydrochloric acid; 5 min in running water; 10 sec each in an ascending alcohol series (50%, 70%, 80% and 95% ethanol);
2 min staining in Orange G solution; 5 sec in 95% ethanol; 2 min staining in Polychrome ea 65 solution; 5 sec each rinsing off the excess dye in three different vessels, each time with 95% ethanol;
2 min immersion in absolute alcohol;
2 min immersion in a 1:1 mixture of absolute alcohol and xylol; and
20 min in xylol.
This prescription obviously is very complicated and time-consuming and can be followed only by trained laboratory personnel.
The problem thus was to find a much simpler and less time-consuming method for differential diagnostic sperm examination that could be carried out even by untrained laboratory personnel.